In the field of beamforming, a receive signal may be composed of M layers. Each of the M layers may be interfered by the M−1 other layers. FIG. 1 shows a beamforming system 100 with an antenna array 103 generating a multi-layered signal 104 for transmission to a mobile device (UE) 105. The antenna array 103 generates the multi-layered signal 104 based on multiple layers 102 received from a layer mapping and precoding module 101.
Joint detection of all M layers would be the optimum solution, which corresponds to a joint M-layer detector as single HW block. Complexity-wise this is not an ideal solution. Typically such “all-layer” detector is only applied for specific subframe configurations and would be a complexity overhead for a majority of subframes, in which less transmitted layers exist in the receive signal. There is a need to design a receiver capable of receiving a multi-layered signal with reduced complexity.